Said Lincecum, in a separate interview: “The only way I’d be up at 4 is if I stayed up all night.”

The Giants’ young All-Star aces aren’t quite the Odd Couple. But if Neil Simon spent five minutes with them, there’s no doubt whom he’d cast as Oscar Madison. The Giants’ version, Lincecum, comes with a knit cap, a skater’s wardrobe, some seriously rebellious hair — and perhaps the best stuff of any pitcher in baseball.

And while Cain isn’t an uptight Felix Unger, his fourth-grade teacher never had to write his name on the blackboard.

His mother should know. It was her classroom.

“He’s always been a good boy,” Dolores Cain said.

The Giants are relevant for the first time in the post-Barry Bonds era, leading the National League wild-card race and holding the third-best record in the league, and it’s largely because of their two horses of a different color: the Tennessee Stud and the Seattle Seabiscuit.

“Yeah, his lifestyle’s probably a little different than mine, but we still get along,” said Lincecum, who will start for the N.L. today. “We listen to the same kinds of music. We play video games and card games on the road.”

Said Cain: “Both of us are pretty open minded. You can’t put anything past either one of us.”

The Giants have two All-Star starting pitchers for the first time since 1966, when Hall of Famers Juan Marichal and Gaylord Perry represented the club. And coincidentally, that game also was staged in St. Louis, when the field temperature at old Busch Stadium famously reached 105 degrees. Marichal and Perry combined to shut out the American League the final five innings, with Perry pitching the ninth and 10th to receive the decision in the N.L.’s 2-1 victory.

Lincecum and Cain have one other All-Star distinction. With identical 10-2 records, they’re the first pair of Giants pitchers to reach double-digit victories at the All-Star break since Bill Swift and John Burkett in 1993.

Both Swift and Burkett reached 20 victories that season. Lincecum was stunned to learn no Giant had reached the 20-win mark since.

“If we keep playing the way we are now, I don’t see why that can’t happen,” he said.

For now, they’ll represent the Giants amid the game’s best players. Cain, a first-time All-Star, will not pitch after getting struck just below the right elbow by a line drive Saturday; Pittsburgh’s Zach Duke replaced him on the active roster. But for a pitcher who entered the season with a 30-43 record and perpetually poor run support, just being in St. Louis is validation enough.

Lincecum is making his second consecutive All-Star appearance, although he was the only player who didn’t play last year in the 15-inning marathon at Yankee Stadium. He never made it to the ballpark because of flu symptoms and extreme dehydration that required a trip to the emergency room.

Cain said he was looking forward to Lincecum showing him the ropes, then joked: “For the first day, anyway. He doesn’t know what happens the second day.”

Lincecum will take no guff from Cain, even though he has a year more service time. Lincecum is quick to point out that he turned 25 in June and Cain won’t be 25 until October.

“I’m the elder,” Lincecum said. “Don’t forget it.”

But Lincecum isn’t above saying he has learned a thing or two from his rotation mate.

“Cainer’s just a big country boy who comes at you with everything he’s got,” Lincecum said. “I love the way he eats up innings and competes, never gives in. I think I’ve learned a lot from him, watching the way he handles himself out there.”

Both of them benefited from intense, personal instruction from the time they were young. Lincecum’s father, Chris, invented the pliant mechanics that allow his son to generate upper-90 mph power from his lithe frame. And Cain worked with former major league pitcher Mauro Gozzo from the time he was young.

“Even from T-ball up, he’s been so competitive,” said Cain’s father, Tom. “He just picked up the game really fast. Even in T-ball, he knew all the rules. He knew where to throw the ball. He had a knack for baseball from Day One. We tried to do everything we could to support him all we could, and send him to get all the instruction he could get.”

Even though Cain won’t pitch, he plans to enjoy the trip. St. Louis is the closest major league city to his hometown of Germantown, Tenn. — about a five-hour drive for Tom Cain, who has a custom woodworking business, and Dolores, who retired from teaching to run her family’s tuxedo rental shop.

Lincecum needed a tux when he accepted the Cy Young Award last year. Perhaps Cain will be using the family discount this time.

Either way, the Giants need both their horses to keep striding down the stretch.

“I hope they continue to do that in the second half,” teammate and 303-game winner Randy Johnson said. “That’s what it’ll take.”